Multi-touch gesture inputs provide an intuitive and efficient user interface for many functions and applications in avionics systems. However, traditional “analog” or finely adjustable multi-touch gestures cannot adequately replace certain input commands where there is a required step-change. For example, map ranges are defined by a set of discrete values selectable by the pilot. These are typically in the order of 2, 5, 10, 20, 50, 100, 200, 500, 1000 miles and are commonly input via knob clicks. Likewise, map orientation can be set to either heading up, track up or North up. These selections are typically input via button selection.
In both cases, an analog multi-touch input does not substitute for the “digital” or highly constrained nature of the existing control scheme. Allowing a continuous map range selection or map orientation selection is incompatible with existing avionics systems.
It would be advantageous to have a touch screen controller and display system that interpreted multi-touch inputs within the constraints of highly constrained, acceptable input values.